There have been known chip-shaped light-emitting diodes having an active layer between a topside electrode and a support substrate, a current-narrowing structure designed so as to centralize driving current in a certain region of the active layer and to induce local emission of light from the certain region of the active layer, and a metal reflection layer for making the light emitted from the active layer toward the substrate side be reflected toward the side of the topside electrode, in which output light is given off via an aperture locally formed in the topside electrode. An example of them is the light-emitting diode disclosed in Patent Document 1. In such a light-emitting diode, among the light rays produced in the active layer, light ray directed to the side of the support substrate is reflected off the metal reflection layer toward the side of the topside electrode. Such a diode therefore has a characteristic of ensuring high light-output efficiency, compared with a highly angle-dependent multilayer film reflection mirror (i.e., DBR layer, which stands for a distributed Bragg reflection layer), and has been utilized as a light sensor, an optical encoder or a point source of light in plastic optical fiber (POF) communications.
Patent Document 1: JP-A-2006-148059